The contest pits the world's leading security researchers against the latest versions of common operating systems and platforms.

In 2009, researchers failed to compromise the iPhone, confounding general expectations. This year, Iozzo and Weinmann had to put in extra effort to bypass the "code signing" and data execution prevention (DEP) technologies that prevent arbitrary code from running on the phone as well as defeat straightforward exploitation of buffer and heap overflow bugs. In order to achieve this result, they chained existing code bits in a technique commonly known as "return-into-libc" or "return-oriented-programming".

It is the first time that this technique has been publicly demonstrated on a real-world telephone. The attack allowed them to execute code on the iPhone when a user visits a malicious website. The demonstrated attack code steals the SMS database from the phone, albeit other attack payloads are easily possible.

The organizers of the contest will communicate the details of the attack to the vendors and will not make the details of the attack public until the vendors can properly patch it.